moonlight-chrome/static/js/background.js

function createWindow(state) {
  chrome.app.window.create('index.html', {
    state: state,
    bounds: {
      width: 960,
      height: 540
    }
  }, function(window) {
    // workaround:
    // state = 'normal' in some cases not work (e.g. starting app from 'chrome://extensions' always open window in fullscreen mode)
    // it requires manually restoring window state to 'normal'
    if (state == 'normal') {
      setTimeout(function() {
        window.restore();
      }, 1000);
    }
  });
}

chrome.app.runtime.onLaunched.addListener(function() {
  console.log('Chrome app runtime launched.');
  var windowState = 'normal';

  if (chrome.storage) {
    // load stored window state
    chrome.storage.sync.get('windowState', function(item) {
      windowState = (item && item.windowState) ?
        item.windowState :
        windowState;
      createWindow(windowState);
    });
  } else {
    createWindow(windowState);
  }
});